Steps for Automating Your Paint Booth with Robots

Q: We are thinking of automating our liquid paint application system, possibly with robots. What are some considerations we should think about before investing in a system?

A: Manufacturing automation is a big – and growing – business. The number of industrial painting robots sold worldwide was expected to reach 400,000 machines a year by 2018, according to the International Federation of Robotics (IFR). The IFR predicts global sales will grow at a year-over-year average rate of 15%.

What drives the paint automation trend? Here are a few things to consider:

Connectivity: There is a strong shift in most industries toward connected technologies, such as smart sensors, vision systems, data analytics software and cloud computing. These are forming the building blocks of the connected manufacturing facility and the smart supply chain.
Integration: Tight integration between the factory floor and enterprise business systems improves manufacturing efficiency and flexibility, and opens the door to the smart factory. As machine-to-machine (M2M) learning grows, the possibilities for integrated manufacturing processes increases.
Analytics: The increasing availability of cloud-based software allows manufacturers to achieve advanced process control and optimization, condition monitoring and predictive analytics. These tools provide real-time data of the production facilities.
Industrial wireless: The growing demand for Internet of Things (IoT) technologies is driving the implementation of industrial wireless and overcoming previous wired limitations. Wireless sensors and IoT devices are becoming increasingly more affordable and advances in cyber security are making wireless a more viable option.

What are the advantages of painting automation?

Cost: Automation and robotic technology is often considered to be too expensive, but the cost of automation is decreasing every year. The initial investment can still be large, but automating a finishing process will increase output while reducing costs and providing benefits for years to come. Overall, developing a long-term plan is essential for manufacturers looking to achieve significant bottom-line savings. Operating with the most energy-efficient equipment available may provide the largest savings, but no opportunity is too small because it all adds up.
Quality: To stay competitive, manufacturers can’t afford to have variation in product quality, especially when it comes to painting. Robots can ensure that the spray gun parameters and spraying motion is exactly the same every time, which increases quality. Even the most skilled painters can’t ensure that type of consistency and precision for each part. Better consistency means less wasted material and higher throughput capabilities.
Technology: Equipment engineered to offer precise mixing and spraying can improve quality; reduce waste and volatile organic compounds (VOCs); and increase overall productivity. Accurate mixing and ratio assurance ensure two-component materials are mixed on demand and at the correct ratio for optimal material performance. Electronic 2K systems have a track record for paying for themselves over time due to savings in waste and time. Using the right spray applicator can also reduce waste and improve overall finish quality.
Less waste: Paint automation can reduce material consumption by up to 30% thanks to the accuracy of robots.
Flexibility: Robots can easily be reprogrammed to do new jobs. Why create a new fixture when a robot can make adjustments on the fly? This flexibility not only saves time during changeovers, it saves money too. Automation also provides flexibility to change materials and colors more frequently, allowing you to simplify your production planning.
Workforce: Robots don’t punch out when the whistle blows and they don’t care if they have to work 24/7. In fact, they can do the work of three employees (three shifts at eight hours per day). For this reason, labor and overhead are usually the largest drivers of savings. Robots benefit the workforce in other ways, such as doing repetitive tasks, which reduces on-the-job injuries and job dissatisfaction. Robots can also remove people from dangerous jobs, allowing them to focus on skilled labor jobs that require decision-making and judgment.

Once you have calculated the value of automation on your paint line, the next step is to determine the machine configuration that best suits your specific application. There are five basic industrial paint automation configurations:

Single station can be semiautomatic, automatic or robotic, and is primarily used for operations that are difficult to accomplish manually. A single station can be simple, low cost and offer good uptime, but it only automates a small number of operations and often requires additional labor.
Continuous machines operate without stopping and perform by moving with the workpiece. Continuous machines lend themselves to very high volume and are mostly dedicated to a particular part. They are durable and quiet, but are fairly complex, which is reflected in their price.
Synchronous machines utilize a mechanism whereby all workpieces are moved together to sequential workstations. They are often preferred when automating relatively high volumes with little changeover or with large lot sizes. They offer a relatively low cost with high speed and the possibility to increase throughput through multiple tooling. However, production is limited to the slowest operation in the sequence.
Nonsynchronous machines use individual workstations that operate independently. They are more suited to higher mix, lower-volume automation projects and the production rate is generally slower than synchronous. However, throughput can be increased by using multiple parts per pallet combined with multiple tooling. Uptime is usually higher than the synchronous alternative due to the independent workstations, and these machines often incorporate programmable changeover in order to accommodate high mix. A key advantage of nonsynchronous machines is flexibility; the equipment is modular so stations can be added, removed or rearranged.
Hybrid industrial automation systems combine synchronous and nonsynchronous machines. With this arrangement, the high speed, throughput and accuracy of a synchronous system can be combined with the flexibility and high uptime of a nonsynchronous system. The disadvantage is that this is usually the most expensive solution and it has a large system footprint.

Automation should be approached as a long-term strategic decision and a great opportunity to redesign your process and explore your entire value stream. For this, a comprehensive automation strategy is necessary.

Bill Heuer is senior product manager for automation for Graco. Visit graco.com/finishing. Source material from drivesncontrols.com, updated with World Robotics Report 2018 info ifr.org